Siren Song
by LindenOwl
Summary: Arthur washes up on shore, and Matthew tries to deal with the cultural differences. Merfolk AU


Matthew watches the white foam recede into the sea, wanting to toe off his boots and wade into the waist deep waters. Instead, he tightens his hold on his almost empty ice cream cone.

"Look, Mattie, it's a shell!" Alfred yells, and Matthew turns around to see his twin brother hold something spiral and white in his hands, "You know what they say."

"That you can hear the ocean inside of it?" Matthew watches Alfred peer into the conch shell, fiddling with his glasses as if that will help him peer through the darkness.

"No- well, yes- but the more exciting thing," Alfred pulls the shell against his ear, and his electric blue eyes light up, "You can hear the merfolk singing from inside of it!"

"Can you?" Matthew pushes the rest of his cone into his cheeks (now they're cold inside and out) and walks up to his brother.

Alfred nods, handing it over. As Matthew fits his ear inside it, he can hear the faint echo of what once must have been a ballad, low and sorrowful, behind the crash of the waves.

Before Matthew can listen to it long enough to decipher the meaning, he feels sticky fingers wrap around the shell and pull it away, Alfred turning the thing over in his hands. Matthew's own feel vaguely empty, sans shell and sans ice cream cone, and he guesses his disappointment shows the next time Alfred looks up.

"If you want it, you can have it," Alfred shrugs, tossing it to Matthew, who catches it with both hands and runs his fingers along the ridges.

* * *

Arthur's new home is alien to him, a choice made by chance rather than desire. Perhaps he thought following the cool currents and seeing where they lead him would calm his buzzing mind, but it has done nothing of the sort; here he is, on the coast of some barren island, cheeks flushed and eyes narrowed, his brother's scornful words still looping between his two ears. He drags himself onto shore, cursing, not for the first time, the heaviness of his fins and tail, the weakness of his chest and arms. Barclay was built like the sandstone statues that lined the edge of their land, and Aislinn could claim strength in her lithe, wiry arms, but there is only one word to describe Arthur: scrawny.

By the time he finds slate to lean his aching body against, his breathing is laboured and it takes effort to sift sand through his fingers. The same substance that lines the ocean floor feels so different on land. Bone-dry and gritty, catching under his fingernails, it brings none of the comfort Arthur wants. Like that, he falls asleep under the weighty gaze of the noonday sun.

* * *

Clouds fall on the sky above the beach, and Matthew huddles further into his raincoat. Without an umbrella- too often too weak against the gales- Matthew relies on an abundance of strings to be pulled and buttons to be buttoned along his torso and arms. It's proven useful over the past few years, despite how Matthew's heart skipped a beat when Alfred showed him the price tag. Though the thought of looking away from the bright yellow material and forgetting (trying to forget) his brother's absence is tempting, Matthew has learned that it does little good. Rather, the last time he fixed his gaze on the shoreline, he only tripped on driftwood and stone.

The rain begins to fall with a moan. Matthew has heard it start with a gentle pitter-patter, or, when the waves churn, a clap of thunder, but he has never heard it start with a moan, followed by a series of pained grunts.

As raindrops stick to Matthew's lenses, he follows the breadcrumb trail of pitiful noises to a merman, clenching and unclenching roughened fists in his sleep. Scrapes line his arms, no doubt from dragging himself onto shore, and Matthew can tell from experience that any saltwater does little to dull the screaming pain.

Matthew steps closer, and two bottle glass green eyes train on his tall form, trapping Matthew, if only for a second. Then, like a set of old blinds, they shutter, harsh and all at once. The sounds stop.

Kneeling at the merman's side, Matthew feels a pulse. That is enough.

Years of hockey practice allow Matthew to pick up the creature, left hand slipping on scales, and begin the trek back to the cabin, to the windows he had left open with white curtains whipping around in the storm winds.

Pale skin and bronze scales remind Matthew of something else the waves had gifted him, years ago, but Matthew knows, something deeper than any logic telling him, that he will have to let this one go.

Matthew stumbles once on his way back, but walks otherwise steady.

* * *

He chose to go back to the beachouse over the summer after Alfred went off to New York and Francis flew to Paris, and Matthew was stuck in the flat the three of them are supposed to share. They'll come back when autumn falls, of course, but the memory still tugs down on Matthew's lips, the air suffocating without Francis' hummed lullabies to bring it levity. To Matthew, those days bring to mind a nightingale in a cage, stuck up there on the fifteenth floor.

So here he is, having planned to play with his paints and read the classics lined up on the shelves, and, instead, pressing a warm cloth to a merman's arm. Matthew turns to click open his first aid kit, thumbing open the clasps and throwing the lid up. When he turns back, the merman's eyes are open. Matthew fights the urge to stare.

"Are you going to sell me?" his voice is smoother than Matthew had expected, but no less weary.

"That's an awful thing to do," Matthew raises the merman's arm, now tense and ready to pull away.

"Humans do it all the same."

"I'm not going to pawn you off," the arm relaxes in Matthew's hands, "You can swim back to your family when you're properly healed."

"I don't need you to bandage me," but the merman's eyes hold a look Matthew has seen more than a few times before, one that says _I wouldn't mind if you disputed me on that point_ , that apparently transcends species (and it makes sense, if pride blossoms in both humans and merfolk.)

"The seawater would burn like hell."

The merman allows Matthew to dab his arm before wrapping it around in gauze.

"My name's Matthew."

"Arthur."

* * *

"I'm not sure what merfolk eat, but I've been having this for the last few weeks," Matthew offers up a bowl of macaroni, not bothering to hide his amusement as Arthur sniffs at it suspiciously.

"There's no blood in this," Arthur frowns, "Are you trying to weaken me further?"

"I just said I've been eating this for the last few weeks."

The way Arthur travels his gaze up and down Matthew's body is unimpressed, to say the least. Matthew repeats the words _cultural differences_ in his head and takes a deep breath.

"I'll see if I have any fish left in the fridge."

Arthur nods, setting his macaroni to the side, and, as Matthew makes to leave the room, a voice catches him, "I apologize if I implied you were weak. I realise you carried me here… and I suppose I never thanked you for that. So, you have my gratitude."

A smile comes to Matthew's face. It's a start.

* * *

It's disconcerting, if Matthew is to be honest, the way every time he glances up at Arthur, Arthur is staring back. Matthew takes a stray piece of paper and tucks it between the pages he's on, putting the book to the side. Arthur stops running his hands over Matthew's kneecaps.

("They're fascinating," he'd said.)

"Would you like to read something? I've got shelves full."

Arthur shakes his head, "Only priests and priestesses can read, and the words are carved on bone, not on hundreds of sheets of whatever that is."

"Oh. Well I suppose it would be hard to build a printing press underwater."

"A what?"

"Nothing. Then you've never read a book?" Matthew raises his to show Arthur what he means.

"No, I've never read a _book_."

Matthew flips open his collection of fairytales, tracing his finger along the spine that holds so many childhood memories, and laughing at the page he lands on: The Little Mermaid.

"I could read to you. I mean, it's just that you look a bit bored."

Arthur struggles to sit up, "I'd like that."

"Okay. Far out into the ocean, where the water is blue as the prettiest cornflower…" Matthew begins, and though his tongue wraps around every word smoothly enough for Arthur not to say anything, Matthew is much more interested in the way Arthur has resumed running his hands over Matthew's shins. Most of Arthur's hands are covered by Matthew's old, grey sweatshirt, the one that was closest to fitting him well, pulled up to the knuckles, and Matthew can feel soft cloth alongside dry fingertips. Arthur is cold like the ocean in spring, and Matthew wonders if this is normal or if he should make Arthur some hot chocolate.

"...and for every tear, a day is added to our time of trial," Matthew finishes, looking up to see that Arthur's pale, thin lips have coalesced into a grin. Even if it is sardonic, Matthew has never seen Arthur smile. It brings a starburst of warmth to Matthew's chest.

"Ridiculous, fading into seafoam, wearing oysters on our tails," Arthur laughs, "Who imagined that up?"

"Well then, how did merfolk come to live in the sea?"

"No one knows," Arthur shrugs, venturing his hands down to tap at Matthew's toes, "All of the legends, they're bold-faced lies, almost as bad as the story you just told, and everyone knows it."

"Then tell me those lies."

Arthur raises one of his bushy brows, "That's the first time someone's asked me for it."

Nonetheless, Arthur takes a quick breath, closes his eyes, and begins to sing with a voice deep and rich, coming with a lilt that Matthew can't quite pinpoint. It soars between notes and dives leagues deep to dark waters, where the sunlight from the surface is obscured, weaving a melody with Matthew's heartstrings, causing his breath to hitch when the song reaches its crest and allowing him reprieve to take in lungfuls of air when it sinks to its troughs.

As Arthur's voice reaches the last bar, Matthew realises that he can't string together the words of the siren song.

(The faint echoes of the conch shell hold nothing to this.)

"Could you repeat that?" colour rises to Matthew's cheeks, and he hurries the rest of his request out, "I got lost in the singing, I'm sorry, it was really good, and I didn't catch the words," Matthew takes a deep breath, "Would you let me write it down?"

 _So I can remember you when you're gone_ , Matthew lets the words hang unspoken in the air.

Arthur takes a long look at Matthew's face, expression earnest and wanting, and his sharp eyes soften, "As long as you don't show anyone else."

* * *

Matthew runs a hand through Arthur's haystack hair, half expecting a needle to prick his finger. The scrapes on Arthur's arms are almost healed, and everywhere that isn't covered in bandages, Matthew can see Arthur's dry skin flaking.

* * *

Arthur allows Matthew to poke at his copper scales, drowsy after drinking too much of a soup Matthew remembers Francis teaching him how to make. The empty bowls lay side by side on the coffee table, a few inches from Matthew's no-longer-prized conch shell. A ritual, Arthur had said; it had probably washed away from some long ago ritual, judging by how faded the voices were.

Arthur turns himself around, drapes over the back of the couch to look out the window, and pauses, "What are those dots in the sky?"

Matthew glances out the window, "The stars?"

"The stars," Arthur rolls the name over in his mouth, "We can't see them from beneath the water, so we never bothered calling them anything."

And in a few minutes, Matthew carries Arthur to a spot closer to the shore so he can see them easier. It's a good night, without the moon to wash anything out, and the stars are scattered liberally over the dark dome of the sky. Wondering what Arthur is feeling, Matthew travels back to his childhood, when he had dreamt the stars were shards of the sun that had snuck their way into the night.

"They're in patterns we call constellations," Matthew sets Arthur down into the sand before sitting down beside him and pointing to some of them, "If you look straight up, the brightest one is Polaris, the North Star, and the spoon looking thing beside it is the Big Dipper, or Ursa Major, though I never quite saw how it was a bear."

Then, Matthew stops, because Arthur's eyes are glazed over with wonderment, their held hands his only anchor to the earth.

"I can imagine you in a crown full of them," Arthur turns back, gaze tender, and Matthew is so far gone he wonders how he never noticed before.

There is nothing to say to that, so Matthew brushes his lips over Arthur's cheek, scratchy, and then lets him soak up the stars.

* * *

Matthew unwraps Arthur's last set of bandages before carrying him over the threshold of what had been their safe haven for the last week or so. The day is clear as Matthew sets Arthur down at the water's edge.

"In case you ever want to return," Matthew pulls out a rolled up map out of his pocket, illustrating the breadth of the Atlantic Ocean, covered in words, mostly out of habit and not out of need.

"I know my way around the north of this ocean," but Arthur's eyes skim the map all the same, drinking up the ink, "What do the words say?"

Matthew traces the lines he'd drawn, "Newfoundland, Greenland, Iceland, Ireland-"

"Humans feel quite fond of this naming scheme, don't they?"

And this does something that should be impossible in the heavy atmosphere of the morning: Matthew smiles.

"What are the words at the bottom?" Arthur asks, because they are larger than any land and crafted with more care.

Arthur looks up into Matthew's eyes and he knows.

(Matthew tastes like syrup and Arthur like salt.)

The two pull apart, and, in silence, Matthew pulls out a small glass bottle, thick rope threaded through the cork, places the map in, and gestures for Arthur to come closer.

Bowing his head, Arthur lets Matthew place his parting present around his neck. The glass is heavy on Arthur's chest.

"Come back next summer, maybe?" and Arthur nods, running slender fingers over Matthew's collarbone.

"I'll miss you," he says, pulling in for another kiss, as if that could bridge the canyon between them. But they both have worlds to get back to, their respective directions away from the no man's land that is the beach. Matthew's eyes hold sorrow, Arthur's, resignation.

And then Arthur pushes himself off and swims away.

"I'll miss you, too," Matthew says to an empty beach, pulling the strings of his hoodie tighter.


End file.
